[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: POSSIBLE FUNCTION OF ORDERLY RINGS OF DINO EGGS? (Was Re: Pubic Pendulum]



Hi Ray,

First of all, thanks for your kind words regarding my dinosaur art, I feel
both honoured and lucky to be involved in this facet of paleontology.
Concerning your idea of decaying vegetation in regards to egg orientation,
it would also then infer that after the eggs have been deposited, the nest
is not further "disturbed" by the parent and are stepping very gingerly
around the clutch.  With some evidence from the fossil record to indicate
nest building and tending of young occurred and that living birds and
crocodilians have the tendency to protect their nests and young, what sort
of suppositions if any can we make about a meticulous system of organization
within the nest and parental monitoring.  This is even more fascinating when
considering the size of the egg-layer and elongate eggs from China.  In
addition to this, one other thing seems puzzling.  If we imagine an
oviraptorid, for instance, depositing eggs one after another while squatting
and each egg having passed through the cloaca ( "pointed end first")
entering into a loose mass of vegetation or churned up substrate, wouldn't
one expect to see the egg oriented with the long axis tilted somewhat (even
a little ) toward the center of the nest and /or the egg layer?  Even if the
egg is then close to vertical, it would then need, sometime after the fact,
to be moved in such a manner that the upper (blunt) end is manipulated past
vertical and then "falls" to the outside, resulting in a ring of eggs, large
ends outward.  Either the dinosaur has to deliberately move the eggs to
achieve this or I'm not understanding something about this process.  Also,
in terms of temperature control, this would seem to be a considerably more
delicate and complex arrangement in producing young than in other
dinosaurian contemporaries that seem to manage with simple unorganized
clutches, or laying eggs in rows of two, etc.  However, we are once again
left with the idea that perhaps in theropods, rotating on an anchored pubis
while egg laying might be a "signature" in recognizing theropod ( with meso
/ propubic condition ) nests.  Can you think of any other examples of
concentric rings of eggs that are known to be non- theropod in nature?  This
is also assuming that all the "rings" in China and Mongolia are oviraptorid
and kin, instead of protoceratopsian.

Mike Skrepnick


>
>
>
>